Significance and sources of vitamin C, food rich with vitamin C, vitamin C bioavailability

1. Domina Petric, MD
Significance and sources of vitamin C

2. Significance of vitamin C
•Redox characteristics allow ascorbic acid
to play an important role, along with
α-tocopherol, reduced glutathione, and
other factors, in the antioxidant
protection of cells.
•Ascorbic acid represents the major
water-soluble antioxidant in plasma
and tissues.
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
24/13/2018

3. Significance of vitamin C
Other beneficial health effects of ascorbic acid
are reductions in:
•hypertension
•atherogenesis
•diabetic complications
•colds and other infections
•carcinogenesis
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
3

4. Distribution in foods
Vitamin C is widely
distributed in both plants and
animals, occurring mostly
(80–90%) as ascorbic acid, but
also as dehydroascorbic acid.
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
4

5. Hawthorn berries: 160-800 mg/100 g
Choosetobehealthy.com
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
5

6. Rose hips: 1000 mg/100 g
Wikipedia.org
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
6

7. Guava: 300 mg/100 g
Exoticflora.in
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
7

8. Other fruit rich with vitamin C
•Apple
•Banana
•Cherry
•Grapefruit
•Melons
•Orange
•Lemon
•Peach
•Raspberry
•Strawberry
•Tangerine
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
8

9. Animal products
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
9

10. Broccoli: 90-150 mg/100 g
Wsj.com
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
10

11. Collard greens: 100-150 mg/100 g
Wikipedia.org
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
11

12. Other vegetables rich with vitamin C
• Asparagus
• Bean
• Cabbage
• Carrot
• Cauliflower
• Celery
• Corn
• Kale
• Leek
• Onion
• Pea
• Parsley
• Pepper
• Potato
• Rhubarb
• Spinach
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
12

13. Stability in foods
• The vitamin C content of most foods
decreases dramatically during storage owing
to the aggregate effects of several processes
by which the vitamin can be destroyed.
• Ascorbic acid is susceptible to oxidation to
dehydroascorbic acid, which itself can be
irreversibly degraded by hydrolytic opening of
the lactone ring to yield 2,3-diketogulonic
acid, which is not biologically active.
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
13

14. Stability in foods
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
14

15. Stability in foods
Losses in cooking are usually greater with such
methods as boiling, because the stability of
ascorbic acid is much less in aqueous solution.
Quick heating methods can protect food
vitamin C by inactivating oxidases.
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
15

16. Vitamin C bioavailability
Vitamin C in most foods appears to have biological
activities comparable to those of purified L-ascorbic
acid at doses in the nutritional range (15–200 mg).
At higher doses bioavailability declines.
Doses greater than 1000 mg appear to be
utilized with roughly 50% efficiency.
4/13/2018
Combs GF. The Vitamins. Fundamental Aspects
in Nutrition and Health. Elsevier Inc. 2008.
16

17. • Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
Literature
4/13/2018 17